In subsea drilling applications, a wear bushing or bore protector is typically installed inside the inner dimension of a subsea wellhead. The purpose of the wear bushing is to protect the critical inner surfaces of the wellhead. Without this protective bushing, tools in the bottom hole assembly (BHA) or the drillstring may come into contact with (and potentially damage) these critical surfaces.
Different sizes of wear bushings are typically required for different hole sections and casing sizes. Therefore, operations typically need to retrieve and run different sizes of wear bushings during the life of drilling the entire well.
For some wellhead systems, a wear bushing running/retrieval tool is not incorporated within the drilling BHA. For such systems, a dedicated trip is required to run and install the wear bushing into the subsea wellhead. Another dedicated trip is then required to retrieve the wear bushing from the subsea wellhead after a section has been drilled. Some examples of running/retrieval tools used for dedicated trips are disclosed in U.S. Pat. No. 8,561,705 and US 2013/0213661. These dedicated trips are time consuming and therefore costly in an offshore drilling environment.
These dedicated running/retrieval trips can be eliminated by using a running/retrieval tool that can be incorporated as a part of the drilling BHA. Such a tool incorporated into the drilling BHA may be used on a stabilizer sub and may have a wear sleeve supported by a bit sub running and retrieval tool. Examples of an incorporated tool include the GE Vetco BRNSP (Bit Run Nominal Seat Protector) and include the tool disclosed in U.S. Pat. No. 6,945,325.
Although running/retrieval tools incorporated into the drilling BHA may be effective, operators are always striving to improve deployment and retrieval steps and to reduce damage to the tool and other problems. To that end, the subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.